Apparatus for separating dust from flue gases



J. ETWANIK Feb. 24, 1942.

APPARATUS FOR SEPARATING DUST FROM FLU E GASES Filed April 25, 1959Fig.4

Inveman- J lRwamH Patented Feb. 24, 1942 APPARATUS FOR SEPAEATI TNG DUSTFROM FLUE GASES Julius. Etwanik, Dusseldorf, Germany, assignor,

by Houston, Tex.

mesne assignments,

to Arthur Burton,

Application April 25, 1939, Serial No. 269,984

7 In Germany April 25, 1938 6 Claims. (Cl. 183-83) The invention relatesto means for separating dust and the like from the flue gases fromboiler or other furnaces before the gases are allowed to escape into theatmosphere.

Apparatus is known in which the separation of the dust particles iseffected by the difference in weight between the gases and theimpurities carried along by them. In one form of such apparatus, theflue gases are led into large settling chambers in which the dust orother particles in the flue gases are deposited iii consequence of thesubstantially reduced velocity.

In another apparatus, large fans are provided for increasing thevelocity of the gases so that the dust particles are thrown out bycentrifugal force.

These known apparatus require considerable space and usually cannot beincorporated in existing plants owing to the lack of space. Apparatusfitted with fans require a constant supply of power and are liable toconsiderable wear and tear.

The subject matter of the invention is characterized by a cylindricalhollow body or a body of similar shape surrounding the lower part of around chimney stack and between this body and the chimney stack isarranged a separating wall, on one side of which lies the inlet openingto the apparatus and on the other side the connecting opening to thechimney stack. When the gases of combustion stream into the annularspace between the chimney stack and the cylindrical hollow body, theflying dust particles con tained in them are thrown against the outerwall of the apparatus in consequence of their centrifugal force andintercepted there.

Advantageously, the cylindrical hollow body or the body of similar shapelies eccentrically to the chimney stack and the separating wall isarranged in the zone of the greatest distance between the hollow bodyand the chimney stack. In consequence of this arrangement, the fluegases first of all stream into a wide part of the annular space and oncircling round the chimney v arating wall 3.

behind the narrowest placev causes the action of centrifugal force to bemore effective.

According to the invention, an intercepting device is provided in frontof the connecting opening, to the chimney stack. This consists of combsor" vanes arranged at an angle to the direction "of the stream, on whichvanes any dust still remaining in the gas is effectively separated.

In order to increase further the separating action according to theinvention, the gases of combustion are led helically downwards in thecylindricalhollow space. This is attained by arranging the bottom of thehollow space so that it slopes in the form of a helix in the directionof the flow of the gases of combustion.

The leading in of the gases of combustion into the outer cylindricalhollow body may be effected both in its upper part and at the foot ofthe same. By leading in the gases of combustion at the foot of thehollow body according to the invention, the gases of combustion withinthe expanded part of the'cylindrical hollow space are led upwards by asecond wall which may be vertical or inclined, or to the upper part ofthe helically shaped sloping bottom of the hollow space.

In the accompanying drawing:

Figure 1 shows a cross section through a chimney shaft with a flue dustseparating apparatus according to the invention.

Figure 2 shows a cross section through a chimney shaft with a modifiedform of separating apparatus.

Figure 3 shows a vertical section through a separating apparatus with anupper inlet for the flue gases.

Figure 4 shows a vertical section through a separating apparatus with alower inlet for the flue gases.

In the drawing, in which similar reference numerals indicatecorresponding parts, a cylindrical hollow body 2 is eccentricallyarranged round the lower part I of a round chimney stack. The chimneystack is connected through a separating wall 3 with the outer hollowbody. The gases of combustion enter by the inlet opening 4 into theenlarged part 5 of a cylindrical hollow space formed by the chimneystack I and the hollow body 2, and on one side of the separating wall,circle round the chimney stack through the contracted part 6 of thehollow space into the second enlarged part I on the other side of thesep- Here are arranged angular combs 8 in front of the separating wallfor the interception of dust particles forced by centrifu gal force tothe outer wall of the hollow space. From this point the gases ofcombustion are led away at an angle to this direction of flow andthrough a connecting opening 9 into the chimney stack. The cylindricalhollow space (5-1) closed at the top is likewise closed below by ahelical bottom l sloping in the direction of flow of the gases, inaddition to which this bottom terminates in a funnel ll below theopening 9. An additional funnel I2 is provided below and behind thecombs 8 for the reception of the flue dust separated at this position.The separated flue dust may be drawn from these funnels by means ofvalves or by a suction draught plant. In the interior of the chimney afurther funnel I3 is provided which may receive any flue dust particleswhich may be separated therein. According to Figure 3, the gases ofcombustion pass through the inlet-opening 4 at the upper part of thecylindrical hollow space. According to Figure 4, the gases of combustionwhich enter below at the foot through the inlet-opening 4 are 'directedupwards within the enlarged part 5 of the hollow space by a secondsubstantially vertical wall I4 and circle round the chimney i above thesloping bottom It], in similar manner as before.

The combs 8 may be constructed of masonry or of iron bent in the form ofan angle. The construction and arrangement of the apparatus for theremainder may be as desired.

I claim:

1. Apparatus for separating dust from flue gas, comprising an uprighttubular member having a cylindrical lower part, a cylindrical hollowbody surrounding said lower part and disposed eccentrically thereto toform therewith a dust separating chamber having a wide part and arestricted part, said chamber having a flue gas inlet and a flue gasoutlet to said tubular member, the inlet and the outlet being arrangedat the wide part of the chamber, a partition wall extending from saidtubular member to the surrounding hollow body, said partitional wallbeing situated adjacent to and between said flue gas inlet and outlet, acomb consisting of angleshaped rods and extending from that edge of theoutlet adjacent to the partition wall across the chamber so as to formthe outer guiding wall for the curved part of the gas stream near theoutlet, said guiding wall intercepting those dust particles stillremaining in the gas, and a dust collecting funnel disposed in the lowerpart of said separating chamber beneath said comb.

2. Apparatus for separating dust from flue gases, comprising avertically disposed tubular member having a cylindrical lower part, acylindrical hollow body surrounding said lower part and disposedeccentrically thereto to form therewith a dust separating chamber havinga wide part and a restricted part, said chamber having a flue gas inlet,and a flue gas outlet to said tubular member, the inlet and the outletbeing arranged at the wide part of the chamber, a partition wallextending from said tubular member to the hollow body across saidchamber and in a position adjacent to and between the flue gas inlet andoutlet, a dust collecting funnel in the lower part on the outlet side ofsaid chamber, a helical bottom extending from the inlet side to theoutlet side and sloping to said collecting funnel, the'outlet lyingspaced above the funnel.

3. Apparatus for separating dust from flue gases, comprising avertically disposed tubular member having a cylindrical lower part, acylindrical hollow body surrounding said lower part and disposedeccentrically thereto to form therewith a dust separating chamber havinga wide part and a restricted part, said chamber having a flue gas inlet,and a flue gas outlet to said tubular member, the inlet and outlet beingarranged at the wide part of the chamber, a partition wall extendingfrom the tubular member to the hollow body across the chamber and in aposition adjacent to and between the flue gas inlet and outlet, dustcollecting funnels disposed along in the lower part on the outlet sideof the chamber, a helical bottom extending from the inlet side to theoutlet side and sloping to said collecting funnels, the outlet lyingspaced above the funnel furthest from the inlet, a comb consisting ofangle-shaped rods and extending above said last mentioned funnel fromthat edge of the outlet adjacent to the partition wall across thechamber so as to form the outer guiding wall for the curved part of theflow of gas near the outlet, said guiding wall intercepting those dustparticles still remaining in the gas.

4. Apparatus for separating dust from flue gases, comprising avertically disposed tubular member having a cylindrical lower part, acylindrical hollow body surrounding said lower part and disposedeccentrically thereto to form there with a dust separating chamberhaving a wide part and a restricted part, said chamber having a flue gasinlet at the lower part thereof, the inlet and the outlet being arrangedat the wide part of the chamber, a flue gas outlet to the said tubularmember, a partition wall extending between said tubular member andhollow body in a position adjacent to and between said flue gas inletand outlet, a dust collecting funnel in the lower part of the outletside of the chamber, a helical bottom extending from a relatively highlevel therein to said dust collecting funnel, and an upwardly extendingwall for directing the gas entering at the low level of the inlet to therelatively high level of said helical bottom.

5. Apparatus for separating dust from flue gas, comprising an uprighttubular member having a lower part with a continuously curved outline, ahollow body having a continuously curved inner wall and surrounding saidlower part, the chamber formed by said hollow body and said tubularmember having an inlet for flue gas and an outlet for flue gas to saidtubular member and a partition wall between said inlet and outlet, andthe cross-sectional area of said chamber on the way from said inlet tosaid outlet first diminishing and then increasing.

6. Apparatus for separating dust from flue gas, an upright tubularmember having a cylindrical lower part, a cylindrical hollow bodysurrounding said lower part and disposed eccentrically thereto to formtherewith a dust separating chamber having a wide part and a restrictedpart, said chamber having an inlet for flue gas arranged at the widepart thereof, an outlet for flue gas to said tubular member alsoarranged at the wide part of said chamber, and a partition wallextending across said separating chamber at a position in the widestpart adjacent to and between the flue gas inlet and outlet to and fromsaid chamber.

JULIUS ETWANIK.

